Human rhinoviruses are a major cause of morbidity, causing >50% of all cases of common colds. ICAM-1 is known to be the receptor for most rhinoviruses and a recombinant, soluble ICAM-1 (sICAM-1) has been shown to be effective in prevention of rhinovirus infection in vitro. Various chimeric (ICAM-1/antibody) immunoadhesins have been shown to effectively inhibit rhinovirus binding to cells. The ICAM-1/IgA immunoadhesin is effective in the nanomolar concentration range. This laboratory has pioneered proprietary methods for the production of secretory IgA antibodies in transgenic plants. SIgA plantibodies are the preferred form of antibody therapy for topical oral or enteric use. The overall goal of the present project is to prepare an sIgA ICAM-1 immunoadhesin plantibody as an economical, stable topical therapy for the common cold caused by rhinoviruses. In Phase I, they will construct secretory IgA ICAM-1 fusion protein expression cassettes, transform alfalfa by particle bombardment and select plans expressing assembled sIgA-ICAM-1 fusion protein. Successful completion of this project will produce a novel therapy for common colds caused by rhinoviruses. PROPOSED COMMERCIAL APPLICATION: Proposed commercial application not available.